Liquefied petroleum gas, e.g., propane or butane, has many uses, which include fuel and heating appliances, cooking equipment and vehicles, including for example, for camping accessories such as stoves, lanterns, and generators of recreational vehicles, and for use by homeowners and proprietors of commercial establishments, for a variety of purposes. Propane and various blends of propane are generally stored in small steel or aluminum bottle containers, which include a discharge valve for fluidly connecting the bottle with lanterns, camp stoves, camping heaters, and similar propane-burning devices. The propane is stored in the bottle under high pressure in a liquid state, typically up to about 150-200 psig. Because propane has a boiling point of −44° Fahrenheit (−42° C.), the liquid propane vaporizes into a propane gas as it exits the bottle. Although there are refillable propane tanks, the typical propane bottle is a DOT 39 cylinder. DOT 39 cylinders are non-refillable, and they must meet certain criteria (for example, ability to withstand the high pressure) established by the Department of Transportation.
Such small LPG bottles are popular among campers, and are used as fuel for a variety of camping accessories. A camper may discard LPG containers after use, when the camper perceives the LPG container(s) to be empty, or at least substantially empty. Substantial numbers of used LPG containers can be discarded each year in recreational areas such as parks, and can result in very large accumulations of the containers. Such LPG and propane bottles pose special problems because if punctured, they could explode, and they cannot be composted along with other, compostable garbage. For example, past reports by one U.S. national park showed an accumulation of tens of thousands of used and discarded propane cylinders, which can create environmental, health and safety hazards.
It can be appreciated that it can be advantageous to extract, or reclaim, the propane from used and discarded containers. It can also be advantageous to recycle the discarded containers, after reclaiming the propane.
U.S. Pat. No. 7,434,506 (Wilson), the disclosure of which is incorporated by reference in its entirety, describes a system for recycle of such bottles. Nevertheless there remains a need to provide for recovery of propane, butane and other LPGs from such bottle containers that is safer, more effective, and more efficient.